BACKGROUND: Behçet's disease (BD) is a multisystemic inflammatory disease. OBJECTIVES: The aim of our study is to investigate whether BD and neuro-Behçet's disease (ND) cause any changes in nasal and olfactory functions. MATERIALS AND METHODS: Our study included 20 patients with BD (group BD), 17 patients with ND (group NB), and a control group of 20 healthy volunteers (group C). Participants underwent nasal endoscopic examination, peak nasal inspiratory flow (PNIF) test to assess nasal airway patency, saccharin test to measure mucociliary clearance and Sniffin' Sticks smell test to assess olfactory dysfunction. RESULTS: In our study, when the groups were examined in terms of saccharin values, it was found to be statistically significantly longer in group BD and group NB ( CONCLUSIONS AND SIGNIFICANCE: The results obtained in this study demonstrate that mucociliary activity and olfactory functions are significantly impaired in both the BD and NB groups.